load the attachmenthttps://www.geogebra.org/m/KrYWuNEv
see the description of the construction
slider - $\displaystyle \alpha$ -select the angle
slider - point P - ruler with a socket, point Q must be line n

on the ruler $AB\infty{_1}\infty{_2}$ , raises divider ADC where AB + AB = AC, ruler sets the angle $\alpha$
semi-line ruler $B\infty{_1}$ sliding on point E , the point A of ruler slides semi-line l , when point C is on the line n , we get the radius of the circle , we get the angle $\beta$
we have solved the tricection of any angle

Look at the construction protocol , or find the error if there is ....